Jig for making pipe elbows



April 14, 1925. 1,533,6 0

L. H. PURNELL JIG FOR MAKING PIPE ELBOWS Filed April 23, 19 2Sheets-Sheet 1 Patented Apr. 14, 1925.

UNITED STA-1E 35mm .OFFICEJQ LEMUEL H. PURNELL',' or CHICAGO, rumors;Assreivon. or ONE-HALF To HEN e. eonm'rz AND ONE-HALF TonNocH PUR-NELL,BOTH. or our PARK, ILLINOIsjare son. mam rxrn BELB'OWS.

Application filed April 23, 192a- Serial No ceases;

T at whom it may concern:

Be it known that I, LEMUEL H. PURNELL, a citizen of the United.States,residing at Chicago, in the county of Cook and State of Illinois,have invented a new and useful Improvement in Jigs for Making PlpElbows, of which the following is a specification. I I I This inventionrelates to jigs for making pipe elbows and the like, and is fullydescribed in the following specificatlon and shown in the accompanyingdrawings, in

which: I j

Fig. 1 is a front. elevation of machine embodying the invention j Fig. 2is an enlarged vertical sect on through the rotary cutters showing apipe in the process of being cut;

Fig. 3 is a vertical.v section through the closing rollers showing't-wosections of pipe being rolled together r Fig. 4: is a sideelevation of a section of pipe showing the jig in place, both of thepipe elbow sections havingbeen cut off Fig. 5 is an enlargedfldetail (ofthe device forclamping the jig about the pipe;

Fig. 6 is a side elevation .of three sections of apipe elbow cut by thismachine;- and Fig. 7 is a side elevation of these same sectionsassembled and turned so asto form a pipe elbow. j

The embodiment of the machine'for carryingout this invention comprises aframe 10 of double C-type in wh-icha shaft 111s suitably jourualed. Aworm wheel 12 1s keyed on this shaft and is driven by a worm 1.3 whichin turn is keyed on the shaft 14 which is driven by a pulley from anysuitable source of power.

The shaft 11 has keyed thereon spur-gears 1(5 and 17. The gear 16 mesheswith a gear 18 keyed on the shaft 19 which is carried in bearings 20 and2 1. The bearing 20 is preferably mounted to rotate about trunnions 2-2while the bearing 21 is movable up and down in suitable guideways 23 bymeans.

of the threaded crank 24.

The shafts 11 and 19 have keyed thereon rotary cutters which areaccurately held against longitudinal movement on the shaft, as shown indetail in Fig.2. The upper cutter consists preferably of. two sections25 and i 26, the former having a cutting edge 25 which passes a similarcutting edge 27 on the lower cutter 27 so that a sheet of metal placed,therebetween will be cut into two sections A and B as shown in Fig. 2. Agroove 27 b is formed in the cutter 27 and a corresponding annularflange 26 is formed upon the cutting member26 so as to form the ogeecurve inthe section A as shown in Fig. 2. A similar groove 25 isformedin the member 25 and a similar flange 28 is formed on the member28 so as to form a reverse curve in the section B.

In order to make elbow sections which can be assembled as will rlater beexplained it is necessary that the cuts between the sections A, B and Cshall each lie ina single plane. In. order to accomplish this, atempl'et or jig 29 is clamped about the pipe by means of a screw 30having right and left hand threads which screw into lugs 31 and 32 whichare secured to the ends of the sheet metal, jig 29. By turning the screw30, the. lugs3l and 32 draw the two ends of the jig tightly about thepipe. A round wire bead 34 is secured by weldinglor brazing to the bodyof the jig 29 and engages a groove 25 inthe member 25. I It will thus beseen that as the cutters are rotated after having been properly adjustedby means of the screw 24, they will be guided about the pipe by the bead34 and the groove 25 so as to make the first cut separating the sectionsA and B. The cutter 25 is raised and the severed end A inserted in thesection B which is held rigid-by the 29. The pipe is then reversed" andthe endsection C is cutand edged in the same way and the end C insertedinto the middle section B.

Then the cuts are thus made it will be found that the outwardly turnededge of the member A can be inserted within the inwardly turned edge ofthe member B as shown in Fig. 3 by inserting one side first and rockingthe other side into position about this first edge as a hinge. Forsomeclasses of work this will be sufiioient to hold the parts together. Inassembling them they are assembled in the same general position as thatshown in Fig. 6. In order to make an elbow of them, each section is thenturned 180 degrees with respect to the next adjacent section with theresult shown in. Fig. 7.

For other classes of work however it has been found necessary to furthercrimp or roll the engaging edges so as to increase the grip of eachuponthe other. For this purpose additinal closijng or crimping rollers 35and 36 are keyed upon the shafts 11 and 37. The shaft 37 corresponds tothe shaft 19 and is mounted and turned in'a similar manner. ,Flanges 36and 36? on. the roller 36 are placed in staggered relation with theflanges 35, the roller 35 and are spaced so as to engage the edgesformed on. the sections A and'B so as to fold the inturned edge of thesection B inwardly and the outwardly turned edge of section A outwardly,thereby mak ing it much more diliicult' to separate these sections.

The flanges of the closing roller-s thus follow the grooves formed inthe pipe and no is required.

The jig 29 performs at least three funct'ions, first, it holds the piperigidly in its cylindrical form and resists the tendency of the cuttersto flatten it out; second, it guides the cutters as has been explained;and third, the friction between the track or bead 34tandthe sides of thegroove 25" forces the metal of the pipe through the cutters. I

Elbows may thus be made of any number of sections from three upwards.\Vhen a three-piece elbow is desired the 29 is formed with a track 3i ateach end. A straight length of pipe is then made of the correct lengthto form all the sections and the clamped to the center of the pipe. Thetwo cuts are then made one after the other by reversing the pipe and inthe cutters. \Vhile the jig is still on the pipe the severed ends areinserted as it holds the pipe rigid.

It is also apparent that this machine may be used to cut fiat sheetmaterial by using a flat jig or templet of the desired shape which issecured to the Hat sheet to be cut.

\Vhi-le I have shown and described but a single embodiment of' myinvention, it is to'be understood that it is capable'of manymodifications. Changes, therefore, in the construction and arrangementmay be made without departing "from ,the spirit and scope of theinvention as disclosed in the appended claims, in which it is myintention to claim all novelty inherent in my invention as broadly aspossible in view of the prior art.

I claim: 7 I

1. A jig for use in cutting off lengths'ot' pipe, comprising a bandadapted to be placed about the pipe, means on the band for causing it togrip the pipe, and means on the band for guiding the cutters.

2. A jig for use in cutting off lengths of pipe, complrising a bandadapted to be placed about the pipe, means for securing said band to thepipe, and means on the band for guiding the cutters.

3. A jig for use in cutting off lengths of pipe, comprising a bandadapted to be placed about the'pipe, means on the band for causing it togri I) the pipe, and a track on the band for gui ing the cutters. 7

4; A jig for use in cutting off lengths'of pipe, comprising a bandadapted to. be placed about the pipe, means on the band for causing itto grip the pipe, said jig being cut at both ends on planes whichdiverge from a plane normal to the axis of the jig, and a track on eachof said ends for guiding a cutter aboutsaid jig. I

5. A jig for use in cutting oil lengths in forming pipe elbow sectionsfrom straight lengths of pipe, said jig having a sheetmetal body, and atrack adapted to cooperate with a pair of rotary cutters to guide themand to force them through the sheet metal of the pipe which is beingcut.

LEMUEL PURNELL.

